Excel Sheet Column Number
A easy-tier problem at 66% community acceptance, tagged with Math, String. Reported in interviews at Docusign and 3 others.
Excel Sheet Column Number is an easy problem that shows up in live assessments at Docusign, Zoho, Razorpay, and TCS. You're given a column label like "A", "Z", "AA", "AB" and need to return its numeric position. The trap is thinking it's base-26 conversion when it's actually a bijective base-26 system. No zero digit exists. If you hit this during an OA and blank on the offset, StealthCoder surfaces a working solution in seconds while your screen stays clean.
Companies that ask "Excel Sheet Column Number"
Excel Sheet Column Number is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Made by a working Amazon engineer who got tired of watching qualified friends bomb OAs they'd solve cold in an IDE.
Get StealthCoderThe problem feels like a string-to-number conversion, so most candidates try treating it as standard base-26 arithmetic. That fails because Excel columns use bijective numeration. There's no zero. "A" maps to 1, not 0. When you see "Z", it's 26, not 25. The pattern: each character contributes (its position in alphabet) times a power of 26, but you must subtract 1 before multiplying the accumulated result by 26 on each iteration. The Math and String topics anchor the solution. Many rush the formula and get off-by-one errors on multi-character inputs like "AA" or "ZZ". If the live assessment throws a tricky label at you and your derivation stalls, StealthCoder runs invisibly and gives you the correct code to paste.
Pattern tags
You know the problem.
Make sure you actually pass it.
Excel Sheet Column Number recycles across companies for a reason. It's easy-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Made by a working Amazon engineer who got tired of watching qualified friends bomb OAs they'd solve cold in an IDE. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Excel Sheet Column Number interview FAQ
Is this actually asked at real companies?+
Yes. Docusign, Zoho, Razorpay, and TCS all report it in their assessment loops. Acceptance rate hovers around 65%, which means candidates who understand the bijective twist pass quickly, but those who force base-26 logic burn time and fail.
What's the actual trick here?+
It's bijective base-26, not standard base-26. There's no zero. Each character is 1-26, and you must adjust the math by subtracting 1 before shifting left. Treat it like a numeral system where A=1, B=2, Z=26, AA=27. That mindset unlocks the formula.
How much does String knowledge help?+
String handling is straightforward. The real challenge is the Math. You need to iterate through characters, extract their alphabet position, and apply the bijective offset correctly. The string iteration is just scaffolding around the mathematical insight.
Will I get this right on the first try if I've drilled it once?+
Probably not. The off-by-one errors are subtle. Even if you've seen it, the live pressure can make you second-guess the offset logic. That's why it sits at 65% acceptance. It's the kind of problem where a hedge matters.
Is this harder than other easy problems on the assessment?+
Not in code length, but yes in conceptual clarity. The bijective base-26 pattern isn't intuitive. Most candidates overthink it or force-fit base-26 rules and fail. If you lock the pattern, it's trivial. If you don't, you're stuck.
Want the actual problem statement? View "Excel Sheet Column Number" on LeetCode →